Apparatus for treating metal sheets



April 2 1940 E. l. HUFF 2,195,816

' APPARATUS FOR TnEA'rIn METAL sums Filed Aug. 2, 1938 6 Sheets-Sheet l April 2, 1940 E. |.y H'uPF 2,195,816

` v Prunus Fon HEATING METAL ,SHEETS Filed Aug. 2. 1938 6 Sheets-Sheet 2 pril 2, 1940. l E, HUFF 2,195,816

lP- RATUS FOR TREATING METAL SHEETS Filed Aug. 2. 1938 6 Sheets-Sheet 3v [Wm/Edy /r/ G. 2 A. VVE/WOA 2 1940. l. HUFF APPARATUS FOR TREATING METAL SHEETS x e f :5I Si g1 :s g sig i//N El i' l April 2. 1940: E. l. HUFF 2,195,816

A APPARATUS ifoR TREATING METAL SHEETS Filed Aug. 2, 1958 6 Sheets-Sheet 6 OIDQZDGIDGIIOCD @mfg/ y Patented Apr. 2, 1949 UNITE-D STATES PATENT Fries APPARATUS FOR TREATING METAL SHEETS Edward I. Huif, Philadelphia, Pa.,- assigner to i Huff Equipment Company, Pittsburgh, Pa., a corporation of 'Pennsylvania Application'August 2, 1938, Serial No. 222,603

20 Claims.

vention relates to a somewhat modified apparatus for carrying out such treatment. The method and apparatus herein described and claimed are of the general type of that described and claimed in my said copending applications, but involves various novel additional features, in particular, the provision of a low temperature heating (or cooling) chamber in which a controlled atmosphere may be maintained, and means for passing the metal sheets through such chamber in their course to and from the high temperature annealing or normalizing chamber.

In the drawings, which illustrate several practical embodiments of myinvention:

Cil

the lower part of a ytwo-stage recuperatiVe-annealing and normalizing furnace in accordance with my invention.

Figure 1B is a corresponding vertical sectional view through the upper part of said furnace.

Figure 2A is avertical sectional view on the line 2 2 in Figure 1A.

Figure 2B is a vertical sectional view on the line 2-2 in Figure 1B. v

3 Figure 3 is a vertical sectional view through a modified typeof two-stage annealing and normalizing furnace in accordance with my invention. l

Figure 4 is a detail view of one of the carrier bars usedin accordance with my invention,

-Figure 5 is a detail View showing the upper edge of a metal sheet'punched with holes for handling in the furnace, and j Figure 6 is a vertical sectional View showing, 45' in part, a modified type of the furnace shown in Figs. 1A and 1B. y

The apparatus shown in Figures 1 and 2 comprises a furnace proper, indicated generally by the reference character l, and divided into an upper high temperature heating chamber and v(and cooling) chamber; a conveyor, indicated generally by the reference character 2, for bringing the sheets of steel to be treated intoposition l'aeneatl'l the furnace; a loading mechanism 3, for loading the sheets of steel on to the conveyor 2; an unloading mechanism 4, for removing' the sheets of s'teel from the conveyor 2 at the completion of the treatment; an elevator y5 carrying out such a method. The present in- Figure 1A is a vertical sectional view through` a rlower low temperature recuperative heating .l

for conveyingthe sheets of steel from the *co'nn veyor 2 upwardly into the low temperature chamber-of the furnace I; conveyors 6 located in the low temperature chamber of the furnace I and adapted to convey the metal sheets through the low temperature chamber and to the entrance to the high temperature chamber; and hoisting mechanism 'I for raising the metal sheets into the high temperature chamber of the furnace.

The furnace I is of more or lessv conventional design,y comprising a framework of metal girders,l

uprights and crosspieces, all indicated by the reference character II, and supporting the usual heat insulating material I3 and refractory material I5. As indicated, the furnace is divided into two chambers, a low temperature chamber' I'I, in which recuperativepreheating takes place, 4and a similar high temperature chamber I9 arranged above the chamber I1. A plurality of electric heating units ZI, ilXed on the interior wall of the high temperature chamber I9, provide the necessary heat. It will be noted'that each heating chamber is substantially entirely enclosed, the only opening from the low temperature chamber being the relatively narrow slot 23 and the only opening from the high temperature chamber I9 being the relatively narrow 255 communicating with the low tempera.-

ture chamber. l l

The conveyor 2 isformed of a pair of endless chain members 3! passing around pairs of sprockets 33and 35, respectively, and supported in the reach-es between the sprockets by angle irons 3T, fixed to upright supports 39. sprockets 33 are xed on a shaft' 4I, journaled in the T-shaped supporting members 43 and sprockets 35 are fixed upon a similar shaft lili, journaled in the supporting members lll. Likewise, fixed on the shaft i5 is a ratchet wheel 49, which is engaged by a lever 5I actingas a pawl. The lever 5I is held in engagement with the ratchet .wheel 49 by a spring 53 attached to the support' 4l. It is pivoted at its opposite end `to a crank disk 55, driven through suitable reduction gearingby an electric motor 59.

The loading mechanism 3 and unloading mechanism l are substantially identical in construction. They each comprise overhead cars 6I traveling on rails t3, supported from and extending beyond the upright girders II of the iurnace'cn each side thereof.

The"

Each cartfi carries electric motor @il and a drum tl driven thereby. A pair of cables 69 are secured to andadapted to be'wound upon each of the drums 6l.

extension '15 formed at its lower end with an inturned, concave flange element 11, which is adapted to receive and hold the ends of the carrier bars hereinafter to be described.

Also secured on each side of the furnace and supported from the rails 63 is an electric motor 'I9 connected through suitable reduction gearing with a crank disk 8|, to which are pivoted the links 83, which links are pivotally secured at their other ends to the cars 6I, so that by rotation of the crank disk 3| through half a revolution the cars SI and associated structure may be caused to move on the rails 63 from the position shown in the dotted lines, in Figure 1A, to that shown in the full lines and vice versa.

The elevator 5 is centrally located in a pit I0, located beneath the conveyor 2. It comprises a pair of channel members 9| forming upright guides, set in recesses I2 formed in the opposite Side walls of the pit A, on which sleeve members 93 positioned and guided by rollers 95 run. To each of the sleeve members 93 is secured an upwardly extending' arm 5l, fitted at its upper end into transversely extending member 99 provided with a pair of sockets |55, each adapted to receive one end of the carrier bars 80 for the metal sheets hereinafter to be described. rlhe sleeve members 93 are operated on the channel members 9| by means of cables |i5| secured thereto, pass ing over pulleys |33 xed at the top of the channel members 9| and secured to and adapted to be wound upon drums |05, positioned at the base of the channel members 9|. The drums |05 are driven by an electric motor ID'I through a shaft |59, journaled in bearings secured to the channel members 9| at their base.

The conveyors G are identical in structure but are driven in opposite directions. Each comprises a pair of endless metal belts |I i. passing around upper sprockets II 3 and lower sprockets II5 and provided with a plurality (in the particular structure shown four on each beit) of eX- tensions II'I, provided with sockets in which the carrier bars 80 for the metal sheets hereinafter to be described, may be engaged and retained. The upper sprockets II3 are xed on two shafts I2!) and I2 I, respectively, which pass through suitable journals |24 secured to the furnace wall and are driven, in opposite directions, by motor |25 located outside of the furnace. The lower sprockets H5 are xed on shafts |22 and |23, respectively, which are journaled in conventional movable bearings |25, supported from the framework |I of the furnace and located within the furnace wall. The movable bearings |25 permit changes in length of the conveyors caused by changes in temperature within the furnace chamber to be taken care of.

The hoisting mechanism comprises a pair of drums ISI secured to a shaft |33 and enclosed in housings |35 located at the top of the furnace I and secured to the upper crosspieces of the supporting framework I. The shaft |33 is driven, through gearing |37 by the electric motor |35. A pair of chains or cables IM are secured to and adapted to be wound upon the drums |.'l| and pass through openings |43 in the roof of a heating chamber I 9. Positioned within this heating chamber i9 and guided in recesses |45 formed centrally of the heating chamber in the side walls thereof is a carrier member |47 which is secured to the lower ends of the chains IAI and is previded with inturned, cup-shaped anges Ille adapted to receive and hold the ends of the carrier bar BIJ for the metal sheets .ereinafter to be described.

Located in the passageway 25 between 'the high temperature chamber 5E and the low temperature chamber Il' are a pair of pivoted guide menibers I5i. These guide members, each of which is generally channel shape but is provided with a aring upper end |53, are supported on shafts |55 set in bearing members positioned in the side walls of the furnace, so that the guide members 55| may be rocked. on the shafts through small angle from the position A shown in. full lines in Figure 1B to the position B shown in dotted lines in this ligure. The guide members 5I may be caused to move from the position A to B and I' inches longer than the desired length and, at

the same time, a plurality of evenly spaced holes are punched along the edge portion oi the sheet. The upper end of such a sheet is shown in Figure 5, the sheet being designated by the reference character 20| and the holes as 253. Of course, it is to be understood that after the sheets have been treated in accordance with my invention, they are sheal'ed along the line 265 and the extra length having the holes punched in it is thus removed. The steel sheets 25S are carried throughout the treatment in the apparatus in accordance with my invention supported on a carrier bar 85. The body portion of this carrier bar is of channel section made of suitable material to withstand the heat to which it is sul jected and designed to absorb the least amount of heat possible. The web of the channel section. will desirably be cored or punched out as shown at 289, in order to reduce the weight thereof. A plurality of hooks 257 are secured at evenly spaced intervals, corresponding with those be tween the holes 2&3 in the steel sheet, to one flange of the channel section either by welding or by being clamped by nuts threaded on the Shanks of the hooks.

In order to illustrate the operation of the apparatus in accordance with this invention, we shall assume that one sheet of steel 25| is being heated in the high temperature chamber I9 and that three sheets of steel are in the low ternperature chamber I'I, all as shown in 1Figures lA and 1B. It will be noted that there are a plurality of steel sheets 285 hanging in the pit I S below the furnace, supported from the carriers 80, which are resting on the conveyor 2. sheets of steel to the left of the furnace opening 3 have not as yet been treated, while those to the right of the furnace opening have been fully heat treated. The carrier 'II of the loading mechanism 3 is in its lowermoa"l position with a carrier bar 85 resting in the flanges l?. The hooks 2Il'! of this particular carrier bar are rmly supported against a fixed bar i2|| secured in the T-shaped supporting members 43. A fresh sheet of steel will now be manually placed on the hooks 25? of this carrier bar Bil.

We now assume that the heat treatment of the metal sheet 20|@ in the high temperature chamber E9 has been completed. The motor I 3E; is accordingly actuated in a direction to rotate the drums I 3| and lower the carrier lll? bearing this particular sheet 26m undergoing treatment. As the sheet descends, pins |51 on each end of the carrier member Ili'l enter and are guided by the aring top |53 of the guides |5| vdistance siuiicient to disengage the flanges lil@ thereof with the carrier bar dil. At th'm moment" the descent of the carrier li'l is stopped and the dotted lines the left hand sockets itil of the elevator 5.

guides l5! are rocked from position A to position B, which brings the cup-shaped nanges of the carrier Ml immediately beneath the carrier bar Sil supporting the metal sheet 2Mb and resting on the extension lll' of the ascending conveyor t closely adjacent the top thereof. The motor E35 is again actuated, this time in the opposite direction, so as to raise the carrier lill, which then picks up the carrier bar Se and the metal sheet Zilli) associated therewith and raises them from the low temperature chamber il up through the guides lol (now in position i3) into the high temperature chamber i9.

While this last operation has been going on the motor |25, driving the conveyors i5, has been actuated to move each of these conveyors, so that the single metal sheet Zillc new carried by the ascending conveyors t is moved from its lower position in the chamber il to the upper position in the chamber Il just evacuated by the sheet 2Mb. At the same time sheet Eels is picked up from the left-hand sockets Hill of the elevator tl (which has been raised into the position shown in dotted lines) rby one of the extensions il? of this conveyor. Meanwhile the descending conveyor 6 will'movethe metal sheet Zuid just deposited thereon from its upper position down into a lower position adjacent the bottom of the chamber il and in so doing will deposit themetal sheet Mild in the right hand sockets lill) ofthe elevator 5, now, as shown in in Figure 1A, in its raised position.

Thefrnotor E will then be stopped, and the elevator 5 operated by actuation of the'motor Sill to lower the carrier har @il carrying the metal sheet Mild on to the conveyor 2 and suific. ntlv further to ,disengage the sockets litl from` the carrier bar ilu. rThe conveyor IZ will then be moved forward by actuation of the motor 5E to an extent suicient to` bring the carrier' bar 3u carrying the metal sheet Milf just above The elevator 5 will then be actuated to raise this carrier har and. the metal sheet 29H to position in the low temperature chamber Il', so that upon the next movement ci the ascending conveyor t csr and metal sheet Zillf will be picked up from sockets lil() of the elevator ii byone of the extension members Hl.

During this last operation motors 55 will be to actuate'the loading mechanism t and unloading mechanism d. The carriers 'll of the loading unloadingmechanism, which will have n in their lowerniost position. 'will thus be elevated the guideways formed by che."'inel members' i3. ln its upward movej ment 'the carrier 'ii of the loading'niechanism 3 will lift with it one of the carrier bars Bil, toge-rhery with metal sheet 2u! just entering the apparatus, which will have been manually placed upon the hooks Zill' as these rest against the supporting bar Ell. The carrier 'll of the ment, carry with it one oi the carrier bars St and the associated metal sheet 2tlg, which was at the extreme right hand position on the conveyor 2 after it had been actuated as described above. When the metal sheets have been lifted suiciently by the carriers 'il to clear vthe con vey'or 2,. the motors $5 are stopped and motor be deposited in the extreme left hand position onconveyor ii, which position will be vacant because of the previous actuation oi the conveyor 2 as described above. At the same time the carrier 'l l. of the unloading mechanism d will deposit the carrier bar k8S and associated metal sheet 2mg in the sockets M3 fixed to the T-shaped support il?. The carriers 'll will thenbe lowered `slightly further until they disengage the carrier bars 8u, in which position the cars Si and their associated structure, including the channel members 73, may be moved back again, by actuation of the motor 79, to the position shown in the solid lines in Figure 1A, when they will be in position for the next cycle of operations. The metal sheetil lg may be manually removed from the carrier bar 8!) resting in sockets '2 i3, and permitted to pass away uponthe rollwa-y M5, upon which it will havel been partly supported. l

The cycle oi operations will new be complete and the metal sheet 2mb, which is now in the high temperature chamber i9, will, when the heat treatment is done, be to be lowered into `position onf-the descending conveyor Si as the iirst step of the second cycle.

It will accordingly be seen that as the cycles continuously follow one another a metal sheet will nrst be manually placed upon the hooks 201 ofY the carrier bar El), resting against the supporting rod ill at the left of the apparatus in Figure 1A; placed by the loading mechanism 3 upon the conveyor 2 in the extreme left hand position; and moved progressively toward the furnace opening as the conveyor 2 is intermittently operated until it comes into position (occupied by sheet Ellie)v beneath the furnace opening 23 and directly abovev the left hand sockets tilt of the elevator 5. It will then be picked up hy the elevator conveyed upwardly into the low temperature furnace chamber Il and kept inl this position (indicated by the dotted sheet 2Mo) until it is picked up by the first actuation of the ascending conveyor t, which, by means of the extensions lil', will pick up this carrier bar and its metal sheet and lift them into theposition occupied by sheet Ellie in Figure 1A. At the next unloading mechanism 5 will, in its upward move-y rockable giudeways |l, will be placed this time upon the extension members ||1 of the descending conveyors S. Ihe rst actuation of the descending conveyor 5 will then lower this sheet I', that has just been heat treated, still within the chamber l1, to the position occupied by sheet 2340i in Figure 1A and upon the second actuation of the descending conveyor 6 the carrier bar with which this metal sheet is associated, will 1o be placed in the right hand sockets |00 of the elevator 5 which, upon being actuated, will lower the carrier bar 93 and the metal sheet back on to conveyor 2. The further intermittent actuation ci conveyor 2 will eventually bring this sheet into tf' iinal right hand position on the conveyor, from which it will be picked up by the carrier 1| ci the unloading mechanism 4, moved over and deposited with its carrier bar resting in the sockets 223, from which position it will :be manually removed.

It of course, obvious that as the heated sheets of metal coming from the high temperature chamber i9 are passing down the descending conveyor 6, they are being cooled under more or less controlled temperature conditions, while the heat given oil? thereby is picked up by the urlreated metal sheets passing up the ascending conveyor E.

In the modification shown in Figure 3 the fur- 80 12e-.ce comprises a large low temperature chamber il', adapted to contain substantially all of the metal sheets undergoing treatment and provided with a high temperature chamber I9 a1'- above the low temperature chamber adc .nt one end thereof. A main conveyor 2 operates within the low temperature chamber |1, being actuated by means of chain 25 driven from pswl and ratchet device 253, located outside of the chamber proper. The pawl and ratchet de- 40, vice is driven through a connection from a piston contained in the cylinder 255 and may be actuated by pneumatic or hydraulic pressure.

The low temperature chamber l1 is completely enclosed, but is provided at each end of its bottern wall with narrow slots 251 and 259, which e as entrances and exits from the chamber,

respectively. The opening 251 is closed by means of a door Eii, operated through link and crank by a motor 253, while opening 259 is closed l5()` by a similar door 295, operated in a similar manner from motor 261.

Located beneath the openings 251 and 259, respectively, are two auxiliary conveyors 289 and Tft', each driven by a pawl and ratchet in the 'ne manner as the main conveyor 2, shown in i gure 1A. Associated with each of these auxiliary conveyors 259, 21| are elevators 213 and 215,

substantially identical in structure with the elevator 5, previously described in connection with the structure shown in Figures 1 and 2. However, the elevators 213 and 215, together with their associated operating motors 211 and 219, secured thereto, are pivotally mounted as at 28|y in the bottom of pits 283 and 285, respectively.

The elevator 213 may thus be tilted out of perpendicular 'oy operation of the motor 281, which drives crank disk 299, which is linked to the upper portion of the elevator supporting structure by shaft 29|. Similarly, the elevator 215 '(0 be moved out of operating position by operation of the motor 293.

There is also provided loading mechanism 3 unloading mechanism 4', substantially idenil with those described in connection with Duros l and 2, operated by means of a motor 19 through crank disk 8|', to which are secured links 83 connecting the crank disk with each of the cars 6|. In operation the loading mechanism 3' lifts a metal sheet to be treated, by means of a carrier bar 80, and places this car- 5 rier bar and metal sheet in extreme left hand position on conveyor 269, the metal sheet extending downwardly into pit 283. The intermediate actuation of the conveyor 209 eventually brings this metal sheet into position immediately upon 10 the sockets |00 of the elevator 213. The carrier bar and associated metal sheet are now raised by the elevator 213, the loading door 26| being rst moved by actuation of the motor 263 to uncover opening 251 up into the low tempera- 15 ture chamber l1', as indicated by the dotted lines in Figure 3. With the elevator in its upward position, motor 281 is now actuated to tilt the elevator together with the metal sheet toward the right (as indicated in the drawing) so that when 20 the motor 2211 is now actuated to lower the elevator, the carrier bar 8i) and the associated metal sheet will be placed upon the conveyor 2 at the extreme leit hand position. The elevator will then be lowered and the door 26| moved back t0 25 close the opening 259.

The continued intermittent operation of conveyor 2 will then move the metal sheet into position directly beneath the hoisting mechanism located at the top of the heating chamber I9 30 which will convey the metal sheet upwardly into the high temperature chamber I9'. After treatment the metal sheet will again be lowered by the hoisting mechanism 1' back into its position upon the conveyor 2. The continued intermittent Il movement of conveyor 2 will then eventually bring the carrier bar 8i) and associated metal sheet to the extreme right hand position on this conveyor. The elevator 215 will then be actuated, having been first tilted, by actuation of 40 the motor 293, into its left hand position, and the door 255 having rst been slid open by actuation of motor 261, so that the rising elevator will lift, by means oi the sockets |00', the carrier bar and associated meta-l sheet from 5 the conveyor 2. The elevator will then be moved back into its right hand position by further actuation of motor 293 and lowered by actuation of motor 219 so as to bring the carrier bar 80 and associated metal sheet upon the auxiliary con- 50 veyor 21| (whereupon the door 265 will be closed).

Further actuation of the conveyor 21| will eventually move the metal sheet in question into position beneath the unloading mechanism 4', 55 which will discharge it from the conveyor.

It will be appreciated that while the actuation of the various electric motors and other mechanism which act to handle the metal sheets in accordance with my invention, from their enm trance into the apparatus until their discharge therefrom, may be, if desired, carried out manually, yet it will ordinarily, in any large scale operation, be desirable to carry out the proper sequence of operations automatically. This may 55 be done by providing a series of interlocking controls and limit switches, as described in my copending application, Serial No. 92,725, -liled July 27, 1936. In this manner each of the electric motors will be automatically stopped and, if nec- 7n essary, made ready to operate in the reverse direction, as soon as it has performed its proper function, and it will be made impossible for any succeeding operation to take place until the preceding operation has been completed. Moreover, 15.

messieif desired, the yentire sequence of operations and the length of time for which the metal sheets are permitted to remain in the high temperature chamber may be controlled by a sequence controller of the type described in my said application.

While the chambers Il, ll have been referred to as low temperature chambers, this designa- Ationin the Itypes of construction hereinbefore the heat given off by the heated metal sheets ser ` through which cooling liquid be circulated:` In this manner the chamber l? may actually be passing therethrough.

However, in accordance with my invention the heat insulation l in these chambers may be dispensed with; and cooling coils, through which brine or otherv cooling liquid may be circulated,

may be placed in Aor upon the wall i3. Such construction is shown inFig.` 6, in which the walls l i3 oi achamber H, otherwise identical with the chamber vl`lhave pipes i8 secured thereto,

kept at substantially atmospheric temperature, so that theV Aheat treated metal sheets passing therethrough may be cooled to .substantially atmospheric temperature in the controlled atmosphere which may be maintained within the chamber il.

lItl will vbe further appreciated that while an v a `lowered into said. second chamber radjacent the electrically heatedfurnace has been described, such furnace may, withinthe scope of my invention,y be heated. in any conventional manner, as by gas, or the like'. Many other modifications of? `my invention will be apparent to those skilledl in the art, and it is accordingly to be understood that my invention is not to be treated as limited to the particular details of constructionl and op- K eration set out above.4

inunicatingtherewith through `said opening, said 'second chamber beingk otherwise closed except at the bottom thereof, conveying means located in said second chamber, other conveying means adapted to travel beneath said second chamber and to carry sheets of metal to be treated, means for raising` said metal sheetsI successively from said second conveying means `upwardly into the` said second chamber, and delivering them to the conveying vmea-ns infsaid chamber, and means adapted to' raise said metal sheets successively from` the 'latter' conveying means up into said first chamber.

2, Apparatus for the treatment of metal sheets'.

including in combination a yfurnace having a heating chamber open only at the bottom thereofy and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath therst chamber vand communicating therewith through said opening,

, said second chamber being otherwise closed except at the bottom thereof, conveying means located insaid second chamber, other conveying means adapted to travel beneath said second chamber and tov carry sheets of metal to be treated, means for raising said metal sheets successively from said second conveying means upwardly into the said second chamber and delivering them to the conveying means in said chamber, and means adapted to raise said metal sheets successively from the latter conveying means up into said nrst chamber and, after heat treatment of each metal sheet in said iirst chamber is `iinished, lower them again into the second chamber and deliver them to the conveyingv means located therein, whereby there are contained, at any one time, in the second chamber, von the s'aid conveying means, both metal sheets that have not been heat treated and ones that have been heat treated.`

3. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof andadapted to vreceive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the first chamber and coml muhicating therewith through said opening, said portion of said conveying means adjacent thev lower end thereof, means forsuccessively removmg treated metal sheets from the descending portion of said conveying means adjacent the lower end thereof, carrier means normally positioned in said first chamber and adapted to be positioned beneath the iirst chamber and communicating therewith through said opening, said second chamber being otherwise closed except` at the bottom thereof, conveying means located in said second chamber comprising a pair of continuous chain. conveyors extending in'a generally vertical direction, each provided with a plurality of means for supporting a metal sheet in dependent vertical position, means for succesv l sively-loading metal sheets to be treated onto one of said conveyors adjacent the lower end thereof, means for' successively removing treated metal sheets from the' second of said conveyors adje-- cent 'the lower end thereof, carrier means nor- `mally positioned in said first chamber and adapted to be lowered into said second chamber to the level of the upper ends of said conveyors and to carry a single metal sheet in dependent vertical position, and movable guide means for said carrier means whereby it may be guided at 5. Apparatus for the treatment of metal sheets including in combination 'a furnace having a heating chamber open only at the bottom thereof and adapted to receive at leasta single sheet of metal positionedfverticallm a second chamber positioned beneath the first chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, a plurality of carrier bars provided with means attachable to an edge of a metal sheet, conveying means located in said second chamber comprising a pair of continuous chain conveyors extending in a generally vertical direction, each provided with a plurality of means for supporting one of said carrier bars, means fo:` successively loading carrier bars supporting metal sheets to be treated onto one of said conveyors adjacent the lower end thereof, means for successively removing carrier bars supporting treated metal sheets from the second of said conveyors adjacent the lower end'thereof, carrier means normally positioned in said first chamber and adapted to be lowered into said second chamber to the level of the upper ends of said conveyors and to engage and support a single carrier bar and associated metal sheet, and movable guide means for said carrier means whereby it may be guided at will into proximity to the upper end of either the first or the second of said conveyors to remove a carrier bar and associated metal sheet from or to place a carrier bar and associated metal sheet upon the said conveyors respectively.

6. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the first chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, conveying means located in said second chamber having ascending and descending portions, means for successively loading metal sheets to be treated onto the ascending portion of said conveying means adjacent the lower end thereof, means for successively removing treated metal sheets from the descending portion of said conveying means adjacent the lower end thereof, carrier means normally positioned in said first chamber and adapted to be lowered into said second chamber adjacent the upper end of said conveying means and to carry a single metal sheet, and pivotable guide means secured in the furnace wall in the opening between said rst and second chambers and adapted to guide said carrier means either to engage and lift an untreated metal sheet from the ascending portion of the said conveying means or to lower and place a treated metal sheet upon the descending portion thereof.

7. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the first chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, conveying means located in said second chamber comprising a pair of continuous chain conveyors extending in a generally vertical direction, each provided with a plurality of means for supporting metal sheet in dependent vertical position, means for successively loading metal sheets to be treated onto one of said conveyors adjacent the lower end thereof7 means for successively removing treated metal sheets from the second of said conveyors adjacent the lower end thereof, carrier means normally positioned in said rst chamber and adapted to be lowered into said second chamber to the level of the upper ends of said conveyors and to carry a single metal sheet in dependent vertical position, and pivotable guide means secured in the furnace wall in the opening between said first and second chambers and adapted to guide said carrier means at will into proximity to the upper end of either the first or the second of said conveyors to remove a metal sheet from or to place a metal sheet upon the said conveyors respectively.

8. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the rst chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, conveying means located in said second chamber, other conveying means comprising a continuous chain conveyor extending horizontally beneath said second chamber and adapted to support a. plurality of metal sheets in vertically dependent position thereon, and elevator means adapted to raise said metal sheets successively from said conveyor into the said second chamber and to transfer them to the said first conveying means located therein.

9. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the first chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, conveying means located in said second chamber, other conveying means comprising a continuous chain conveyor extending horizontally beneath said second chamber and adapted to support a plurality of metal sheets in vertically dependent position thereon, and elevator means adapted in its upward movement to raise one of said metal sheets from said conveyor into the said second chamber and into position to be picked up by the said rst conveying means located therein, said elevator means While in its raised position being adapted to receive another metal sheet from said rst conveying means, and

in its downward movement lower said sheet onto the said horizontal chain conveyor.

l0. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the rst chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, a plurality of carrier bars provided with means attachable to an edge of a metal sheet, conveying means located in said second chamber, other conveying means comprising a continuous chain conveyor extending horizontally beneath said second chamber and adapted to support thereon a plurality of carrier bars supporting metal sheets in vertically dependent position, and elevator means adapted to raise said carrier bars and associated metal sheets successively from said conveyor into the said second chamber and to transfer them to the said rst conveying means located therein.

11. Apparatus for the treatment of metal sheets including in combination a furnace having a heat- 75 ing chamber open only. at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the first chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, a plurality of carrier bars provided with means attachable to an edge of a metal sheet, conveying means located in said second chamber, other conveying means comprising a continuous chain conveyor extending horizontally beneath said second chamber and adapted to support thereon a plurality of carrier bars supporting metal sheets in vertically dependent position, and elevator means adapted in its upto be picked up bythe said first conveying means located therein, said elevator means while in its raised position being adapted to receive another carrier bar and associated metal sheet from said first conveying means, and in its downward movement lower said carrier bar and associatedmetal sheet onto the said horizontal chain conveyor.

12. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the` bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the rst chamber and communicating therewith through said opening, said second chamber being otherwise Iclosed except at the bottom thereof, conveying means located in said second chamber having ascending and descending portions, other conveying means comprising a continuous chain conveyor extending horizontally beneath said second chamber and adapted to supporta plurality of metal sheets in vertically dependent position thereon, and elevator means adapted to raise said metal sheets successively from said conveyor into the said second chamber and to transfer them to the ascending portion of said conveying means adjacent the lower end thereof, said elevator means also serving to successively remove treated metal sheets from the descending portion of said conveying means adjacent th-e lower end thereof and lower them onto the said horizontal chain conveyor, carrier means normally positioned in said first chamber and adapted to `be lowered into said second chamber ladjacent the upper end'of said conveying means and to carry a single metal sheet, and movable guide means for said carrier means whereby it may be guided either to engage and lift an untreated metal sheet from the ascending portion of the said conveying means or to lower and place a treated metal sheet uponk of the said pairs of conveyors upwardly into the descending portion thereof.

13. Apparatus for the treatment of metal sheets including in combination a furnace havingl a heating chamber open only at the bottom thereof and adapted to receive Aat least a single sheet of metal positioned vertically, a second chamber positioned beneath the first chamber and communicatihg therewith through said opening, said second chamber being Aotherwise closed except at the bottom thereof, conveying means located in said second chamber comprising a pair of continuous chain conveyors extending in a generally vertical direction., each provided with a plurality of means for supporting a metal sheet in dependent verti'cal position, other conveying means comprising a continuous chain conveyor extending horizontally beneath said second chamber and adapted to lsupport a plurality of metal sheets in vertically dependent position thereon, and elevator means adapted in its upward movement to raise one of said metal sheets from said horizontal conveyor into the said second chamber and into position to be picked up by one of said vertical conveyors adjacent the lower end thereof, said elevator means while in its raised position being adapted to receive another metal sheet from the second of said vertical conveyors adjacent the lower end thereof, and in its downward movement low-er said sheet onto the said horizontal chainl conveyor, carrier means normally posi- Ationed in said first chamber and adapted to be lowered into said second chamber to the level of the upper ends of said vertical conveyors and to carry a single metal sheet in dependent vertical position, and movable guide means for said carrier means whereby it may be guided at will into proximity to the upper end of either the first or the second of said vertical conveyors to remove a metal sheet from or to place a metal sheet upon thev said conveyors respectively.

. 14. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned .beneath the first chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottorn thereof, conveying means located in said second chamber comprising a continuous chain conveyor extending horizontally Within said chamber, other conveying means adapted to travel beneath said second chamber and to carry sheets of metal to be treated, and means for raising said metal sheets successively from said second rconveying means upwardly into said second chamber and delivering them to said horizontal chain conveyor adjacent one end thereof.

15. Apparatus for the treatment of metal sheets including iny combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheetl of metal positioned vertically, a second chamber positioned beneath the first chamber and com-v municating therewith through said opening, said 'second chamber being otherwise closed except -at the bottom thereof, conveying means located in said second chamber comprising a continuous chain conveyor extending horizontally within said chamber, other conveying means comprising a pair of continuous chain conveyors located beneath said second chamber adjacent each end thereof and adapted to carry metal sheets in vertically dependent position, elevator meahs for raising one of said metal sheets from one said second chamber and delivering it to the said horizontal chain conveyor adjacent one end thereof, and a second elevator means for raising one 4of said metal sheets from said horizontal conat the bottom thereof', a plurality of carrier bars provided with means attachable to an edge of a metal sheet, conveying means located in said second chamber comprising a continuous chain conveyor extending horizontally within said chamber and adapted to support a plurality of carrier bars and associated metal sheets, other conveying means comprising a pair of continuous chain conveyors located beneath said second chamber adjacent each end thereof and adapted to carry a plurality of carrier bars supporting metal sheets in vertically 'dependent position, elevator means for raising one of said carrier bars and metal sheets from one of the said pairs of conveyors upwardly into said second chamber and depositing the carrier bar and metal sheet upon the said horizontal chain conveyor adjacent one end thereof, and a second elevator means for raising one of said carrier bars and metal sheets from said horizontal conveyor adjacent the opposite end thereof, lowering said carrier bar and sheet from the said second chamber and depositing the carrier bar and metal sheet upon other of the said pair of conveyors located beneath the chamber.

17. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the first chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, a plurality of carrier bars provided with means attachable to an edge of a metal sheet, conveying means located in said second chamber comprising a continuous chain conveyor extending horizontally within said chamber and adapted to support a plurality of carrier bars and associated metal sheets, other conveying means comprising a pair of continuous chain conveyors located beneath said second chamber adjacent each end thereof and adapted to carry a plurality of carrier bars supporting metal sheets in vertically dependent position, elevator means for raising one of said carrier bars and metal sheets from one of the said pairs of conveyors upwardly into said second chamber and depositing the carrier bar and metal sheet upon the said horizontal chain conveyor adjacent one end thereof, and a second elevator means for raising one of said carrier bars and metal sheets from said horizontal conveyor adjacent the opposite end thereof, lowering said carrier bar and sheet from the said second chamber and depositing the carrier bar and metal sheet upon other of the said pair of conveyors located beneath the chamber, said elevator means having means associated therewith for moving at least the upper portions thereof horizontally.

18. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically,a second chamberpositioned beneath the rst chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, a plurality of carrier bars provided with means attachable to an edge of a metal sheet, conveying means located in said second chamber comprising a continuous chain conveyor extending horizontally Within said chamber and adapted to support a plurality o1'y carrier bars and associated metal sheets, other conveying means comprising a pair of continuous chain conveyors located beneath said second chamber adjacent each end thereof and adapted to carry a plurality of carrier bars supporting metal sheets in vertically dependent position, elevator means for raising one of said carrier bars and metal sheets from one of the said pairs of conveyors upwardly into said second chamber and depositing the carrier bar and metal sheet upon the said horizontal chain conveyor adjacent one end thereof, and a second elevator means for raising one of said carrier bars and metal sheets from said horizontal conveyor adjacent the opposite end thereof, lowering said carrier bar and sheet from the said second chamber and depositing the carrier bar and metal sheet upon other of the said pair of conveyors located beneath the chamber, and means at least partly positioned in said rst chamber and adapted to raise said metal sheets successively from the said horizontal chain conveyor up into said rst chamber.

19. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the first chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, means for cooling said second chamber, conveying means located in said second chamber, other conveying means adapted to travel beneath said second chamber and so carry sheets of metal to be treated, means for raising said metal sheets successively from said second conveying means upwardly into the said second chamber and delivering them to the conveying means in said chamber, and means adapted to raise said metal sheets successively from the latter conveying means up into said first chamber.

20. Apparatus for the treatment of metal sheets including in combination a furnace having a heating chamber open only at the bottom thereof and adapted to receive at least a single sheet of metal positioned vertically, a second chamber positioned beneath the rst chamber and communicating therewith through said opening, said second chamber being otherwise closed except at the bottom thereof, means for cooling said second chamber, conveying means located in said second chamber, other conveying means adapted to travel beneath said second chamber and to carry sheets of metal to be treated, means for raising said metal sheets successively from said second conveying means upwardly into the said second chamber and delivering them to the conveying means in said chamber, and means adapted to raise said metal sheets successively from the latter conveying means up into said first chamber and, after heat treatment of each metal sheet in said first chamber is nished, lower them again into the second chamber and delivel-'them to the conveying means located therein, whereby there are contained, at any one time, in the second chamber, on the said conveying means, both metal sheets that have not been heat treated and ones that have been heated treated.

EDWARD I. HUFF. 

